2. Physics 114 Professor Fred Salsbury Office Hours: Tuesday 4-5 pm and Thursday 2:30-3:30 pm, or by appointment in 301A Olin Tutorials : TBA http://www.wfu.edu/~salsbufr http://www.webassign.net salsbufr@wfu.edu Topics Covered Electricity and Magnetism Nuclear Physics Please Pick Up and READ the Course Policies, Syllabus and Voting Cards

3. Class Participation Bring your voting cards to every class period If you forget them, borrow some from me If you lose them, get new ones from me Do you understand how the voting system works? A)Yes, I’ve done it before B)Yes, though it is new to me C)Sort of, I’ll figure it out D)No, I am totally confused I will give extra credit points for productive class participation.

4. Assignments Reading Assignments: on Webassign Every lecture Reading quizzes, due 7am before lecture STARTING THURSDAY Covering reading and review: typically 3-5 MC/essays ~5 submissions: Work by yourself Homework: on Webassign Due every T/Th 10pm; STARTING TUESDAY Will include review of vectors and calculus Typically 4-5 problems ~10 submissions: Encouraged to work with others Quizzes and Final Quantitative questions, qualitative questions and derivations. If you miss any quiz/exam, I need a note from a medical doctor or the Dean’s office. Lowest Semester quiz is work ½ credit

5. Webassign http://www.webassign.net/student.html Username is your email (without @wfu.edu) Institution is wfu Password (if new to webassign) is your student number Without leading zeros If you have used webassign before use your old password. Log into webassign ASAP. Do the Survey and webassign HW If you have difficulty, contact me. There is a test homework on using webassign.

6. Grading Final Exam 330 points Best 3 Semester Quizzes 300 points Homework and Reading Quizzes 300 points Worst Semester Quiz 50 points Laboratory 20 points You must pass lab to pass the course. You are expected to pass the final to pass the class. Productive class participation will earn extra points. This course is not “curved”. This course is not graded on a 10 point scale. Each assignment will have cutoffs and the cutoffs are averaged. If the course is significantly off track, then the last quiz will be cancelled.

7. Content This class has a substantial mathematical component, and is calculus-based.  11.5 lectures on electricity  Ch. 22-28  1.5 lectures on nuclear physics  Ch. 43  8.5 on magnetism and electromagnetic waves  Ch 29-34  If time permits, additional topics in optics  Some additional topics {e.g. geometric optics and additional electronics} will be covered in lab

8. Web Information How to access course info: Go to www.wfu.edu/~salsbufr Click on teaching, then on Phy114A2005 There will be a page for general announcements, and a sidebar Lectures notes will be posted on the web page, as are the syllabus and course policies. If you have trouble using it, contact me!

9. Coordinate systems Different ways of representing space, and physics. Some problems are easier in some coordinate systems, but the physics is invariant. Cartesian Coordinates:

10. Polar Coordinates Another popular coordinate system along with cylindrical and spherical

11. Vectors: Magnitude and direction Scalars: Magnitude Vectors and Scalars Displacement is a vector. Velocity is a vector. Acceleration is a vector.

12. The x- and y-components of a vector: The magnitude of a vector: The angle  between vector and x-axis: Vector Components: Geometric

13. A = A x i + A y j Vector Components: Algebraic A unit vector is a dimensionless vector having a magnitude 1. Unit vectors are used to indicate a direction. i, j, k represent unit vectors along the x-, y- and z- direction. is another common notation. i, j, k form a right-handed coordinate system.

14. We want to calculate:R = A + B From diagram:R = (A x i + A y j) + (B x i + B y j) R = (A x + B x )i + (A y + By)j Vector Addition: Algebraic I R x = A x + B x R y = A y + B y The components of R:

15. The magnitude of R: The angle  between vector R and x-axis: Vector Addition: Algebraic II

16. Vector Multiplication There are two ways (in 2 or 3D) to multiply vectors. Scalar product -> two vectors make a scalar Vector product -> two vectors make a vector Also called the dot product or the inner product Also called the cross product or the outer product

17. Scalar Product Scalar product -> two vectors make a scalar Geometric Algebraic

18. Vector Product Vector product -> two vectors make a vector Geometric Algebraic C has magnitude absin  Direction perpendicular to the plane containing A and B.

19. The right hand rule velocity v Magnetic Field B Force F

20. Electricity and Magnetism One of the four fundamental forces of nature Responsible for the vast majority of what we observe around us Probably best-understood and best-tested of the forces of nature Electromagnetic Interactions: Electricity and Electronics Magnetism Chemistry Biology and even more

21. Electrical Charges Electric forces only affect objects with charge Charge is measured in Coulombs (C). A Coulomb is a lot of charge! Charge comes in both positive and negative quantities Charge is conserved – it can neither be created nor destroyed Charge is usually denoted by the letter q. An object has a total charge of 5  C. It is divided into two pieces, one of which has charge 8  C and the other of which has charge A)3  C B)-3  C C)13  C D)Such a division is impossible

22. Charge Densities Charge can be localized to discrete points (point charges), or it may be spread out over a volume, a surface or a line Charge density  units C/m 3 Surface charge density  units C/m 2 Linear charge density units C/m A cube with side 1 cm has a charge density of  = 1 C/m 3. What is the charge of the cube? A)1 C B)0.01 C = 10 mC C)10 -4 C = 100  C D)10 -6 C = 1  C 1 cm

23. Some ways to charge objects By rubbing dissimilar objects By physical contact between a charge and a conductor By proximity between a charge and a conductor – charging by induction By chemical processes + - +